The infant drop-in clinic actually recommended we use a dummy. They showed us a DVD called "The Happiest Baby on the Block" which went through a list of settling techniques. I'd never even thought about using a dummy but we bought one of the way home and when we put it in DD's little mouth it was almost like "oh... THAT'S what I've been wanting" and she fell asleep.
I've never really paid much attention to dummies before but the funniest thing is that DD wiggles it around just like the baby on the Simpsons.
DD never confused the dummy and the bottle. She would make complaining noises if she was hungry and we gave her a dummy instead of a bottle.